Figure 1.

(Data reformatted from Reference [28]). Retention of tritiated-25(OH)D3 in C2 myotubes, C2 myoblasts and MG63 osteoblasts. Cells were incubated for 16 h with [26,27-³H]25-hydroxyvitamin D3 (Perkin Elmer, Waltham, MA, USA) in Dulbecco’s Modified Eagle’s Medium (DMEM) supplemented with serum replacement (Sigma-Aldrich, St. Louis, MO, USA) followed by 3x washes with ice cold Phosphate Buffered Saline (PBS). At this point, 0 h or 4 h later, cells were harvested, lysed, and assayed for protein by the bicinchoninic acid assay (Thermo-Scientific, Bannockburn, IL, USA) or radioactivity counted by liquid scintillation counting (see Reference [28]). Data as mean counts per minute (CPM) ± Standard Error of the Mean (SEM) (n = 3 wells/group).